1 /*
2  * Copyright (c) 2000 Silicon Graphics, Inc.  All Rights Reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms of version 2 of the GNU General Public License as
6  * published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it would be useful, but
9  * WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
11  *
12  * Further, this software is distributed without any warranty that it is
13  * free of the rightful claim of any third person regarding infringement
14  * or the like.  Any license provided herein, whether implied or
15  * otherwise, applies only to this software file.  Patent licenses, if
16  * any, provided herein do not apply to combinations of this program with
17  * other software, or any other product whatsoever.
18  *
19  * You should have received a copy of the GNU General Public License along
20  * with this program; if not, write the Free Software Foundation, Inc., 59
21  * Temple Place - Suite 330, Boston MA 02111-1307, USA.
22  *
23  * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
24  * Mountain View, CA  94043, or:
25  *
26  * http://www.sgi.com
27  *
28  * For further information regarding this notice, see:
29  *
30  * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
31  */
32 #ifndef __XFS_IALLOC_H__
33 #define	__XFS_IALLOC_H__
34 
35 struct xfs_buf;
36 struct xfs_dinode;
37 struct xfs_mount;
38 struct xfs_trans;
39 
40 /*
41  * Allocation parameters for inode allocation.
42  */
43 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_IALLOC_INODES)
44 int xfs_ialloc_inodes(struct xfs_mount *mp);
45 #define	XFS_IALLOC_INODES(mp)	xfs_ialloc_inodes(mp)
46 #else
47 #define	XFS_IALLOC_INODES(mp)	((mp)->m_ialloc_inos)
48 #endif
49 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_IALLOC_BLOCKS)
50 xfs_extlen_t xfs_ialloc_blocks(struct xfs_mount *mp);
51 #define	XFS_IALLOC_BLOCKS(mp)	xfs_ialloc_blocks(mp)
52 #else
53 #define	XFS_IALLOC_BLOCKS(mp)	((mp)->m_ialloc_blks)
54 #endif
55 
56 /*
57  * For small block file systems, move inodes in clusters of this size.
58  * When we don't have a lot of memory, however, we go a bit smaller
59  * to reduce the number of AGI and ialloc btree blocks we need to keep
60  * around for xfs_dilocate().  We choose which one to use in
61  * xfs_mount_int().
62  */
63 #define	XFS_INODE_BIG_CLUSTER_SIZE	8192
64 #define	XFS_INODE_SMALL_CLUSTER_SIZE	4096
65 #define	XFS_INODE_CLUSTER_SIZE(mp)	(mp)->m_inode_cluster_size
66 
67 /*
68  * Make an inode pointer out of the buffer/offset.
69  */
70 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_MAKE_IPTR)
71 struct xfs_dinode *xfs_make_iptr(struct xfs_mount *mp, struct xfs_buf *b, int o);
72 #define	XFS_MAKE_IPTR(mp,b,o)		xfs_make_iptr(mp,b,o)
73 #else
74 #define	XFS_MAKE_IPTR(mp,b,o) \
75 	((xfs_dinode_t *)(xfs_buf_offset(b, (o) << (mp)->m_sb.sb_inodelog)))
76 #endif
77 
78 /*
79  * Find a free (set) bit in the inode bitmask.
80  */
81 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_IALLOC_FIND_FREE)
82 int xfs_ialloc_find_free(xfs_inofree_t *fp);
83 #define	XFS_IALLOC_FIND_FREE(fp)	xfs_ialloc_find_free(fp)
84 #else
85 #define	XFS_IALLOC_FIND_FREE(fp)	xfs_lowbit64(*(fp))
86 #endif
87 
88 
89 #ifdef __KERNEL__
90 
91 /*
92  * Prototypes for visible xfs_ialloc.c routines.
93  */
94 
95 /*
96  * Allocate an inode on disk.
97  * Mode is used to tell whether the new inode will need space, and whether
98  * it is a directory.
99  *
100  * To work within the constraint of one allocation per transaction,
101  * xfs_dialloc() is designed to be called twice if it has to do an
102  * allocation to make more free inodes.  If an inode is
103  * available without an allocation, agbp would be set to the current
104  * agbp and alloc_done set to false.
105  * If an allocation needed to be done, agbp would be set to the
106  * inode header of the allocation group and alloc_done set to true.
107  * The caller should then commit the current transaction and allocate a new
108  * transaction.  xfs_dialloc() should then be called again with
109  * the agbp value returned from the previous call.
110  *
111  * Once we successfully pick an inode its number is returned and the
112  * on-disk data structures are updated.  The inode itself is not read
113  * in, since doing so would break ordering constraints with xfs_reclaim.
114  *
115  * *agbp should be set to NULL on the first call, *alloc_done set to FALSE.
116  */
117 int					/* error */
118 xfs_dialloc(
119 	struct xfs_trans *tp,		/* transaction pointer */
120 	xfs_ino_t	parent,		/* parent inode (directory) */
121 	mode_t		mode,		/* mode bits for new inode */
122 	int		okalloc,	/* ok to allocate more space */
123 	struct xfs_buf	**agbp,		/* buf for a.g. inode header */
124 	boolean_t	*alloc_done,	/* an allocation was done to replenish
125 					   the free inodes */
126 	xfs_ino_t	*inop);		/* inode number allocated */
127 
128 /*
129  * Free disk inode.  Carefully avoids touching the incore inode, all
130  * manipulations incore are the caller's responsibility.
131  * The on-disk inode is not changed by this operation, only the
132  * btree (free inode mask) is changed.
133  */
134 int					/* error */
135 xfs_difree(
136 	struct xfs_trans *tp,		/* transaction pointer */
137 	xfs_ino_t	inode,		/* inode to be freed */
138 	struct xfs_bmap_free *flist,	/* extents to free */
139 	int		*delete,	/* set if inode cluster was deleted */
140 	xfs_ino_t	*first_ino);	/* first inode in deleted cluster */
141 
142 /*
143  * Return the location of the inode in bno/len/off,
144  * for mapping it into a buffer.
145  */
146 int
147 xfs_dilocate(
148 	struct xfs_mount *mp,		/* file system mount structure */
149 	struct xfs_trans *tp,		/* transaction pointer */
150 	xfs_ino_t	ino,		/* inode to locate */
151 	xfs_fsblock_t	*bno,		/* output: block containing inode */
152 	int		*len,		/* output: num blocks in cluster*/
153 	int		*off,		/* output: index in block of inode */
154 	uint		flags);		/* flags for inode btree lookup */
155 
156 /*
157  * Compute and fill in value of m_in_maxlevels.
158  */
159 void
160 xfs_ialloc_compute_maxlevels(
161 	struct xfs_mount *mp);		/* file system mount structure */
162 
163 /*
164  * Log specified fields for the ag hdr (inode section)
165  */
166 void
167 xfs_ialloc_log_agi(
168 	struct xfs_trans *tp,		/* transaction pointer */
169 	struct xfs_buf	*bp,		/* allocation group header buffer */
170 	int		fields);	/* bitmask of fields to log */
171 
172 /*
173  * Read in the allocation group header (inode allocation section)
174  */
175 int					/* error */
176 xfs_ialloc_read_agi(
177 	struct xfs_mount *mp,		/* file system mount structure */
178 	struct xfs_trans *tp,		/* transaction pointer */
179 	xfs_agnumber_t	agno,		/* allocation group number */
180 	struct xfs_buf	**bpp);		/* allocation group hdr buf */
181 
182 #endif	/* __KERNEL__ */
183 
184 #endif	/* __XFS_IALLOC_H__ */
185